For filling, in a large bowl, cream butter and sugars until light and fluffy. Beat in milk and vanilla. Gradually beat in flour. Stir in mini chocolate chips. Spread over brownies (works best to just press out with clean hands.); chill until firm.

For glaze, in a microwave safe bowl, melt chocolate chips and shortening in 30 second intervals, stirring after each time, until smooth. Spread over filling. Immediately sprinkle with nuts, pressing down slightly. Yields 3 dozen.